2 Chronicles 30:1-3

1Hezekiah then sent word to all Israel and Judah, and also wrote letters to Ephraim and Manasseh to come to the House of Adonai at Jerusalem to keep the Passover for Adonai, the God of Israel.

2The king and his officials and the entire congregation in Jerusalem had decided to celebrate Passover in the second month.

3For they were not able to celebrate it at the regular time, since not enough kohanim had consecrated themselves, nor had the people assembled in Jerusalem.